The present invention relates to a cover structure for a circular saw blade of an electric power circular saw. Also, it relates to a cut waste or debris discharging device for a circular saw.
A conventional cover for an electric power circular saw is shown in FIG. 20. Namely, the cover structure includes a safety cover 2 for covering an upper portion of a circular saw blade 1, a lower guard 3 that is angularly movable into the safety cover 2 in accordance with the advancement of cutting operation of a workpiece by the circular saw 1 and a front cover 4 having a substantially U-shaped cross section covering a waste generating portion at the front portion of the circular saw blade 1.
With such a structure, the cut waste or debris generated by cutting the workpiece A with the circular saw blade 1 is led to a discharge port 5 to thereby prevent the waste from being splashed to the outside.
However, such a conventional cover structure suffers from a problem that the waste would also flow in directions indicated by arrows a in FIG. 20 when the waste flows from a front portion to a rear portion of the safety cover 2 within a flow path within the safety cover 2. The waste which flows in the direction indicated by the arrows a will splash through parts except for the discharge port of the safety cover 2 and would not be collected to a desired portion.
Also, at the front portion of the safety cover 2, there is a gap 7 between a reference plate 6 (or the workpiece A) and a front cover 4. Accordingly, the conventional structure also suffers from such a problem that a part of the waste generated at the cutting portion would flow in the directions indicated by the arrows b. Also, a part of the waste would enter into the interior of the lower guard 3 which has been advanced toward the front cover 4 through the safety cover 2 in accordance with the development of the cutting work.
FIG. 21 shows a conventional cut waste discharging device. More specifically, a guide wall 13 for guiding cutting debris or waste is provided in an interior of a safety cover 2 for covering a cutting saw blade 1. A discharge outlet 14 is provided at a side wall of the safety cover 2 for discharging the waste which has been guided by the guide wall 13. The waste generated in the cutting portion is discharged to the outside from the discharge outlet 14 while flowing in directions indicated by a number of arrows c and being guided by the guide wall 13.
However, with such a structure of the conventional waste discharging device, there is a fear that the cut waste would fall within the safety cover 2 or would be entrained by the rotation of the cutting saw blade 1 while falling within the safety cover 2 without directing to the discharge outlet 14. For this reason, a large amount of waste is splashed until the waste reaches the discharge outlet 14. Accordingly, the amount of waste collected through the discharge outlet 14 is reduced by these phenomena.